填空题 refreshing leak indispensable be mindful ofseal tear off socket lumber cumbersome munch fold commodity 1. Crude oil is the world's most important ________. 2. Although the machine looks ______, it is actually easy to use. 3. She was becoming _______ to him. 4. We had to ________ every step we took on slippery sidewalk. 5. They slapped together a cabin out of old _____. 6. The water was cold and wonderfully ______. 7. Check _______ on fridges and freezers regularly. 8. He put the electric plug into the ______. 9. Luke ______ the chicken sandwiches. 10. The contents of the report were ______ to the press